1. Field of the Invention
The present invention relates to a card connector assembly which is double-decked with a combination of two card connectors, e.g. upper and lower, to insert a card from outside, and which has a card misinsertion preventive structure.
2. Description of the Related Art
Generally, in electronic apparatus such as a printer, a card connector is used into which a card such as a semiconductor memory card is inserted from outside. Such electronic apparatus has a controller for controlling the connection between the card connector and the card inserted in the card connector so as to make it possible, for example, to read data recorded on the card.
Conventionally, in such electronic apparatus, a card misinsertion preventive structure having e.g. a shutter provided at the insertion opening of a card connector has been proposed to prevent a foreign object from being inserted into the card connector from outside. For example, Japanese Laid-open Patent Publication Hei 9-266028 discloses a card misinsertion preventive structure for a card connector, in which an elongated rectangular-shaped shutter is pivotally mounted on a holder of the card connector. The shutter closes or covers the insertion opening of the card connector in the absence of a card inserted in the card connector so as to prevent a foreign object from entering the card connector.
It is to be noted here that there are various standards for cards, and cards vary in e.g. shape and number of contacts for respective standards. Accordingly, card connectors have various shapes depending on the card standards. Thus, some of the electronic apparatus have a double-decked card connector assembly having upper and lower card connectors so as to be adaptable to multiple different card standards. However, for the purpose of cost reduction, such electronic apparatus may have only one controller for controlling the connection between a card and the card connector assembly. More specifically, when a card is inserted into either one of the upper and lower card connectors, the controller controls the connection between the card and the card connector having the card inserted therein. Since only one controller is present, it is not possible to control connections between the card connector assembly and multiple (two) cards at the same time.
This causes a problem because it is possible to insert multiple cards into the card connector assembly at the same time, regardless of the presence or absence of a shutter, for the following reason. First assume that no shutter is provided on either one of the card connectors (first and second card connectors) in the card connector assembly. Under this assumption, even if a card is inserted into a first card connector, the insertion opening of a second card connector is open, so that a further or second card can be inserted into the second card connector from outside. Next assume that shutters, each as disclosed in the above-described Patent Publication, are provided on the respective card connectors in the card connector assembly. In this case, the shutters should be assumed to be independently provided on the card connectors so as to be independently openable and closable. Under this assumption also, even if a first card is inserted into a first card connector, it is possible to insert a second card into a second card connector.
If two cards can be inserted at the same time into both card connectors of a card connector assembly in an electronic apparatus having only one controller, a user may misunderstand that both cards can be connected to both card connectors at the same time, even though the electronic apparatus has only one controller. Actually, however, only one card inserted into one card connector can be connected to the one card connector. This may cause misinsertion of cards. If a second card is erroneously inserted into a second card connector after a first card is inserted into a first card connector, it causes a connection error with the second card, and the controller does not function with the second card. This connection error provides discomfort to the user, and impairs comfort in using the electronic apparatus.